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PubMed2004

Comparison of initial shear bond strengths of plastic and metal brackets.

The aims of this study were to compare initial and 24 hour shear bond strengths of plastic brackets with a mechanical base (Spirit MB) and metal brackets, using two different adhesives (System 1+ and Enlight), and to examine the modes of failure after debonding. Eighty extracted human premolars were used. After bonding, shear bond strengths in half the sample were tested within 30 minutes. The remaining 50 per cent were placed in a 37 degrees C distilled water bath for 24 hours before testing. The results showed that the effects of the two adhesives and the interaction of the two time intervals and the two bracket types on shear bond strength were significantly different (P < 0.05 and P < 0.0001, respectively). Six of the 10 groups were found to have less than 50 per cent of the adhesive remaining on the tooth surface after debonding in the 24 hour metal bracket-System 1+ group, but most specimens in the other seven groups had more than 50 per cent of the adhesive left. It is concluded that System 1+ cannot provide sufficient initial bond strengthfor Spirit MB and may increase the risk of enamel fracture for metal brackets.

Adhesives↗
PubMedDate not supplied

Effects of dentin disinfectants on the shear bond strength of all-ceramics to dentin.

This study investigated the effect of dentin disinfectants on the shear bond strength of all-ceramic restorations luted with two different dual-polymerizing systems to dentin. Dentin disinfectants chlorhexidine gluconate-based Concepsis and benzalkonium chloride-based Tubulicid Red were applied in combination with Variolink 2 and Resilute. The buccal surfaces of non-carious extracted human premolars were flattened to expose dentin and subsequently polished with 600-grit wet silicon carbide paper. Each dual-polymerizing luting system had two test groups and a control group. Dentin from the test groups was first treated with dentin disinfectants, then the all-ceramic restorations were luted with dual polymerizing systems. The dentin without disinfectant application and ceramic restoration was used as a control. After the all-ceramic samples were luted to all treated surfaces, the specimens were thermocycled and tested for shear bond strength until failure. Analysis of the fractured dentin surfaces was performed using Optical Microscope-Nikon ECLIPSE ME 600 (Nikon Co, Tokyo, Japan) at between 10x and 1000x magnifications and the images were analyzed with Image Analyzer LUCIA 4.21 (Nikon Co). The data were analyzed with one-way ANOVA and Duncan test at a significance level of p<0.05. Application of the two dentin disinfectants increased the shear bond strength of both the Variolink 2 and Resilute systems, but this increase was statistically significant only in Tubulicid Red treated specimens (p<0.05). Surface analysis showed that all the specimens showed the adhesive failure mode between the dentin and composite luting agent interface.

Acid Etching, Dental↗
PubMedDate not supplied

Shear bond strengths of three different resin luting cements to bovine teeth.

This study evaluated the shear bond strengths of dentin/porcelain and enamel/ porcelain specimens bonded with three different dual-cure cements. The specimens were prepared using the heat-pressed ceramic technique. Three different dual-cure cements were used to bond samples to previously prepared bovine enamel and dentin surfaces. The specimens were thermocycled and tested in shear until failure. The shearbond data was subjected to one-way ANOVA, followed by Duncan's multiple range test at a significance level of p < 0.05. The shear bond strengths of Variolink II were significantly higher than those of Rely-X ARC and Panavia F for enamel and dentin (p < 0.05). Bond strenghts in enamel were higher than those of dentin in all materials (p < 0.05).

Analysis of Variance↗
PubMed2006

Shear bond strength of metal-ceramic repair systems.

STATEMENT OF PROBLEM: When clinical fractures of the ceramic veneer on metal-ceramic prostheses can be repaired, the need for remake may be eliminated or postponed. Many different ceramic repair materials are available, and bond strength data are necessary for predicting the success of a given repair system. PURPOSE: This study evaluated the shear bond strength of different repair systems for metal-ceramic restorations applied on metal and porcelain. MATERIAL AND METHODS: Fifty cylindrical specimens (9 x 3 mm) were fabricated in a nickel-chromium alloy (Vera Bond II) and 50 in feldspathic porcelain (Noritake). Metal (M) and porcelain (P) specimens were embedded in a polyvinyl chloride (PVC) ring and received 1 of the following bonding and resin composite repair systems (n=10): Clearfil SE Bond/Clearfil AP-X (CL), Bistite II DC/Palfique (BT), CoJet Sand/Z100 (CJ), Scotchbond Multipurpose Plus/Z100 (SB) (control group), or CoJet Sand plus Scotchbond Multipurpose Plus/Z100 (CJSB). The specimens were stored in distilled water for 24 hours at 37 degrees C, thermal cycled (1000 cycles at 5 degrees C to 55 degrees C), and stored at 37 degrees C for 8 days. Shear bond tests between the metal or ceramic specimens and repair systems were performed in a mechanical testing machine with a crosshead speed of 0.5 mm/min. Mean shear bond strength values (MPa) were submitted to 1-way ANOVA and Tukey honestly significant difference tests (alpha=.05). Each specimen was examined under a stereoscopic lens with x30 magnification, and mode of failure was classified as adhesive, cohesive, or a combination. RESULTS: On metal, the mean shear bond strength values for the groups were as follows: MCL, 18.40 +/- 2.88(b); MBT, 8.57 +/- 1.00(d); MCJ, 25.24 +/- 3.46(a); MSB, 16.26 +/- 3.09(bc); and MCJSB, 13.11 +/- 1.24(c). On porcelain, the mean shear bond strength values of each group were as follows: PCL, 16.91 +/- 2.22(b); PBT, 18.04 +/- 3.23(ab); PCJ, 19.54 +/- 3.77(ab); PSB, 21.05 +/- 3.22(a); and PCJSB, 16.18 +/- 1.71(b). Within each substrate, identical superscript letters denote no significant differences among groups. CONCLUSIONS: The bond strength for the metal substrate was significantly higher using the CJ system. For porcelain, SB, CJ, and BT systems showed the highest shear bond strength values, and only SB was significantly different compared to CL and CJSB (P<.05). CLINICAL IMPLICATIONS: This study suggests that when fracture involves only feldspathic porcelain, any of the evaluated systems may be used, since the fracture occurred on the porcelain substrate and not on the bond interface of porcelain-restorative material. However, for the nickel-chromium alloy tested, the CoJet Sand system showed the best results for repair.

Analysis of Variance↗
PubMed2002

The effect of saliva contamination on shear bond strength of orthodontic brackets when using a self-etch primer.

The purpose of this study was to assess the effect of saliva contamination on the shear bond strength of orthodontic brackets, at various stages of the bonding procedure using a new self-etch primer. Brackets were bonded to 52 extracted human molars according to one of the following four protocols. Group I (uncontaminated control): A self-etch acidic primer, Angel I (3M/ESPE Minneapolis, Minn) was placed on the enamel for 15 seconds, gently dried with air, and light cured for 10 seconds. Precoated brackets APC II (3M Unitek, Monrovia, Calif) were then placed on the teeth and light cured for 20 seconds. Group II: The enamel surface was first contaminated with human saliva for 10 seconds, blown off with an air syringe for five seconds. The bonding procedure was then repeated as in group I. Group III: The self-etch primer was applied for 15 seconds, gently dried with air, and light cured for 10 seconds. The surface was then contaminated with human saliva for 10 seconds, blown off with an air syringe for five seconds. The precoated brackets were then bonded as in groups I and II. Group IV: The enamel surface was contaminated with human saliva for 10 seconds, blown off with an air syringe for five seconds. The self-etch primer was applied. The surface was then re-contaminated with human saliva for 10 seconds, blown off with an air-syringe for five seconds. The precoated brackets were then bonded as in groups I, II, and III. The results of the analysis of variance (F = 4.79) indicated that the shear bond strengths of the four groups were significantly different (P = .005). Tukey HSD tests indicated that contamination both before and after the application of the acid-etch primer resulted in a significantly lower (=1.7+/-1.4 MPa) shear bond strength than either the control group (=6.0+/-3.5 MPa) or the groups where contamination occurred either before (=4.8+/-3.3 MPa) or after (=4.8+/-3.3 MPa) the application of the primer. The new acid-etch primer can maintain adequate shear bond strength if contamination occurs either before or after the application of the primer. On the other hand, contamination both before and after the application of the primer significantly reduced the shear bond strength of orthodontic brackets.

Acid Etching, Dental↗
PubMed2000

In vitro shear bond strength of orthodontic bondings without liquid resin.

This study aimed at evaluating the early shear bond strength of enamel-composite-bracket adhesion accomplished without the use of liquid resin. Orthodontic brackets were bonded to the buccal surfaces of healthy extracted premolars in the test group by Transbond XT (n = 8) and Phase II (n = 8) composites but not the enclosed liquid resins in these products. Brackets bonded with the same materials (n = 8 for each) along with their corresponding liquid resin served as controls. The specimens were tested for shear bond strength after 24-h storage in water at 37 degrees C. The fractured surfaces were graded with Adhesive Remnant Index (ARI) under a 2x-dissection microscope. Enamel of the randomly selected test and control specimens was dissolved by 20% formic acid. Afterwards, the enamel side of the bonding materials in both groups (n = 4) was examined under the scanning electron microscope. ANOVA was used for statistical analyses. Our laboratory data suggest that the enamel adhesion produced by these two commercial materials without the use of liquid resin does not differ significantly in their early in vitro shear bond strength.

Acrylic Resins↗
PubMed1995

Ex vivo shear bond strength of fibreglass reinforced aesthetic brackets.

Fibreglass reinforced brackets (FGBs) and ceramic brackets were bonded to the enamel of extracted premolars to evaluate their shear bond strength and fracture mode. One-hundred extracted premolars were divided into five groups, and combinations of two-paste and no-mix composite, and plastic bracket conditioner were used in the test groups. Bond strength testing was carried out 24 hours after direct bonding. The shear strength of ceramic brackets with a two-paste composite was significantly higher than FGBs bonded with either two-mix or no-mix composite ( P < 0.05). Ceramic brackets bonded with two-mix and no-mix composite demonstrated a 30 and a 10 percent enamel fracture rate, respectively. There were no enamel or bracket fractures in any of the FGB groups.

Bicuspid↗
PubMedDate not supplied

Shear bond strength of repaired composite resins using a hybrid composite resin.

The shear bond strength of different types of composite resins repaired with a hybrid composite was evaluated. The hybrid composite resin was repaired with itself as a control. The results of this study showed that the shear bond strength of the repair with most types of composite resins was minimally adequate.

Analysis of Variance↗
PubMed2003

Comparison of shear bond strength of composite, compomer and resin modified glass ionomer in primary and permanent teeth: an in vitro study.

The aim of this study was to determine the difference in shear bond strength between Composite, Compomer and Resin modified glass ionomer cement in primary and permanent teeth. Thirty extracted primary molars and thirty premolars were selected and buccal surfaces of all the teeth were made smooth with the help of 300 grit silicon carbide paper. These specimens were then divided into 6 groups. Restorative materials were placed on the buccal surfaces of respective specimens with the help of acrylic template. All the specimens were subjected to thermocycling and shear bond strength was tested under the Honsfield testing machine and results were recorded in megapascals (MPa). The resultant scores were tabulated and statistically analysed. It was observed that in case of primary teeth resin modified glass ionomer exhibited significantly higher shear bond strength as compared to composite and compomer, where as on permanent teeth composite demonstrated a significantly higher shear bond strength than that of the resin modified glass ionomer and compomer, where as compomer gave poor shear bond strength in both primary and permanent teeth.

Bicuspid↗
PubMed1995

Shear bond strength and quantitative microleakage of a multipurpose dental adhesive system resin bonded to dentin.

The shear bond strengths of a dental bonding system used in conjunction with a composite resin bonded to dentin were determined 1 minute after irradiation and after storage in saline at 37 degrees C for 24 hours, 1 week without and with temperature cycling, and 4 weeks without and with temperature cycling. The quantitative microleakage of class V preparations in cementum (dentin) restored with the system was determined by a spectrophotometric dye-recovery method. Excellent shear bond strengths ranging from 13.9 MPa (1 minute) to 19.5 MPa (1 week) were obtained. The shear bond strengths and quantitative microleakage of the multipurpose dental adhesive system compared favorably with the data obtained from other dental bonding systems under similar experimental conditions.

Analysis of Variance↗
PubMed2006

Shear bond strength of calcium phosphate ceramic brackets to human enamel.

The aim of this study was to examine the shear bond strength between Hyaline brackets, a new type of calcium phosphate ceramic bracket, and human enamel using various types of adhesive resin and to investigate the effectiveness of a silane-coupling agent to bond Hyaline to human enamel. Kurasper F, Light Bond, Super Bond C&B, and Transbond XT were used as adhesive resins, and Porcelain Liner M was used as the silane-coupling agent. The Hyaline bracket was bonded to human enamel using one of the above adhesive resins according to the manufacturer's instructions. After applying the Porcelain Liner M to Hyaline, the Hyaline bracket was also bonded to enamel using one of the above adhesive resins according to the manufacturer's instructions. The shear bond strengths were measured after immersion in water at 37 degrees C for 24 hours. Three types of adhesive resin, Kurasper F, Light Bond, and Super Bond C&B, produced clinically acceptable shear bond strength with and without Porcelain Liner M. Transbond XT produced significantly lower bond strength to enamel with or without Porcelain Liner M (P < .05). The application of Porcelain Liner M was not useful for improving the bond strength of Hyaline to enamel. The adhesive remnant indices were not significantly different among four adhesive resins. In conclusion, adhesive resins such as Kurasper F, Light bond, and Super Bond C&B are useful for bonding esthetic Hyaline brackets to human enamel.

Analysis of Variance↗
PubMed1998

Effect of enamel and dentin surface wetness on shear bond strength of composites.

PURPOSE: This study investigated the effect of the wetness of human enamel and dentin surfaces on the shear bond strength of composites. MATERIAL AND METHODS: Seven dentin bonding systems were used. Three methods of preparing the enamel or dentin surface before applying primer or bonding agent were adopted as test conditions: wet (blot dried), semidry (3-second air blast), and dry (15-second air drying). Shear bond strength was measured with a universal testing machine. Mean bond strengths were analyzed with analysis of variance and Scheffe's F-test. Enamel and dentin surfaces were observed by a dissecting microscope after shear bond testing. RESULTS: Enamel specimens tested by all systems and dentin tested by two systems did not reveal significant differences in shear bond strengths (p > 0.05). Among dentin specimens tested by two systems with water-based primers, the shear bond strength values of the dry technique group were higher than those of the other two groups (p < 0.05). However, among dentin specimens tested by systems having acetone-based primers or bonding agents, bond strength values of the wet or semidry technique groups were higher than those of the dry technique group (p < 0.05). CONCLUSION: It was concluded that some water might be needed by dentin surfaces or for primers to obtain high bond strength on the dentin surface, but that drying methods did not affect bonding strength to enamel surfaces either before priming or after conditioning.

Analysis of Variance↗
PubMedDate not supplied

Bonding indirect resin composites to metal: Part 1. Comparison of shear bond strengths between different metal-resin bonding systems and a metal-ceramic system.

PURPOSE: This laboratory study compared the shear bond strength between three indirect resin composites and a noble alloy using their respective bonding systems. MATERIALS AND METHODS: One hundred twenty disks cast in a medium-gold, high-noble metal-ceramic alloy (V-Deltaloy) were divided equally into four groups and received different treatments for veneering: Conventional feldspathic porcelain (Omega) was applied on one set of specimens to be used as a control, and three indirect resin composites (Artglass, Sculpture, Targis) with their respective bonding systems were used for the other groups. The specimens were tested in a parallel shear test, half of them after 24-hour dry storage at room temperature and the rest after 10-day storage in normal saline solution at 37 degrees C and thermocycling. The fractured specimens were evaluated to determine the nature of the failure. RESULTS: The mean shear bond strength values (in MPa), before and after wet storage and thermocycling, were 30 and 23 for the metal-ceramic group, 29 and 23 for the Artglass group, 20 and 19 for the Sculpture group, and 17 and 14 for the Targis group, respectively. The metal-ceramic and Artglass groups exhibited significantly higher bond strengths than the other two groups. All specimens, with the exception of the Sculpture group, showed a significant decrease in bond strength after wet storage and thermocycling. CONCLUSION: No group exceeded the shear bond strength of the metal-ceramic group, but the Artglass group with its respective metal-resin bonding system exhibited similar bond strengths. The Sculpture group showed a stable bond after water storage and thermocycling.

Aluminum Silicates↗
PubMed1999

In vitro comparison of 10-minute versus 24-hour shear bond strengths of six dentin bonding systems.

OBJECTIVE: Early bond strengths produced by dentin bonding systems should be sufficient to resist the polymerization shrinkage of resin composite. This study compared the 10-minute and 24-hour shear bond strengths of six dentin bonding systems: One-Step (OS), PermaQuik (PQ), Prime & Bond 2.1 (PB), Scotchbond Multi-Purpose (SBMP), Single Bond (SB), and Tenure Quik with Fluoride (TQ). METHOD AND MATERIALS: Each bonding system was used to bond composite to visibly moist dentin at 34 degrees C +/- 2 degrees C. The specimens were debonded at 37 degrees C +/- 1 degree C 10 minutes after the start of light curing of the bonding system, and the results were compared with the 24-hour bond strengths. The mode of failure was recorded. RESULTS: The 10-minute mean shear bond strengths were: OS, 16.4; PQ, 14.3; SB, 14.0; PB, 12.7; TQ, 10.7; and SBMP, 9.3 MPa. The 24-hour mean shear bond strengths were OS, 23.3; PB, 20.8; SB, 20.3; PQ, 19.4; TQ, 11.2; and SBMP, 10.0 MPa. The 10-minute mean shear bond strengths of OS, PQ, PB, and SB bonding systems were significantly less than the 24-hour values. More dentinal fractures and mixed failures were observed with OS, PQ, and PB. Systems with higher bond strengths had more resin penetration into the lateral dentinal branches. CONCLUSION: The 10-minute mean shear bond strengths were all less than 17 MPa, and the 10-minute bond strengths were less than the 24-hour values.

Bisphenol A-Glycidyl Methacrylate↗
PubMed2004

Does plasma irradiation improve shear bond strength of acrylic resin to cobalt-chromium alloy?

OBJECTIVES: Plasma treatment leads to surface modification such as the improved wettability of dental materials. Studies have suggested that plasma treatment may bring about an improvement in the shear bond strength between cobalt-chromium alloy and self-curing acrylic resin. METHODS: Forty-eight cobalt-chromium alloy specimens were randomly divided into four groups (each of the groups consisted of 12 specimens); air abrasion, adhesive primer, adhesive primer after air abrasion, or after plasma irradiation. A self-curing acrylic resin, 2 mm thick and 3.6 mm in diameter, was processed on all specimens before storage in distilled water at 37 degrees C for 24 h. Shear bond strength values were determined at a crosshead speed of 0.5 mm/min. Data was statistically analyzed using Scheffé's test. RESULTS: Adhesive primer clearly increased the shear bond strength compared with air abrasion (p < 0.05). The synergy of air abrasion and adhesive primer greatly increased the shear bond strength, showing a five-fold increase over air abrasion, or one and a half-fold over adhesive primer. A similar tendency in increase was observed in the adhesive primer after plasma treatment, but to a lower degree. Adhesive primer after plasma treatment showed half the shear bond strength of the treatment of adhesive primer after air abrasion (p < 0.05). Moreover, adhesive primer after plasma treatment showed a lower shear bond strength than adhesive primer alone although the difference was not statistically significant. SIGNIFICANCE: Plasma treatment does not improve adhesion between cobalt-chromium alloy and self-curing acrylic resin.

Acrylic Resins↗
PubMed2006

Effect of different bonding conditions on the shear bond strength of two compomers to bovine dentin.

AIM: Despite the improvements to compomer materials, the bond strength of these materials remains inferior to "composite/resin bonding" systems and limits their clinical use. The purpose of this study was to evaluate the effect of acidic conditioning with phosphoric acid and Prompt L-Pop (PLP) on the shear bond strength of two compomers Dyract AP (DAP) and Composan Glass (CG) to dentin. METHODS AND MATERIALS: Sixty extracted bovine teeth were used to test the shear bond strength of two compomers to flat dentin labial surfaces. The dentin specimens were randomly assigned to six groups of ten specimens each: Group 1: DAP and Prime & Bond NT (PBNT); Group 2: DAP/PBNT with a 15 second dentin etch prior to bonding; Group 3: DAP placed with PLP adhesive; Group 4: CG and Compobond NE (CBNE); Group 5: CG/CBNE with a 15 second dentin etch; and Group 6: CG placed with PLP adhesive. The specimens were stored at 37 masculineC with 100% humidity for 24 hours then mounted and sheared using an Instron Universal Testing Machine at a cross head speed of 0.5 mm/min. The results were recorded in Mega Pascals (MPa). The sheared specimens were examined under a light microscope, and the type of failure (adhesive, cohesive, or mixed) was recorded. RESULTS: The mean dentin shear bond strength value (MPa) for the groups was: Group 1 (11.6+/-3.9); Group 2 (13.2+/-3.3); Group 3 (12.4+/-2.0); Group 4 (13.0+/-4.3); Group 5 (19.3+/-3.7); and Group 6 (13.1+/-3.0). One way analysis of variance (ANOVA) and Tukey HSD post-hoc tests detected a significantly higher bond strength (P = 0.003) for group 5. For groups 1, 3, 4, and 6, the mode of failure was mostly adhesive. When acid etching of dentin was performed (groups 2 and 5), cohesive fracture within dentin was the predominant mode of failure. Acid etching and the use of PLP significantly reduced the number of adhesive fractures and reduced variability in the shear bond strength results. CONCLUSIONS: Acid etching significantly increased the shear bond strength of CG to dentin but did not affect DAP. The application of PLP resulted in a shear bond strength not statistically different from PBNT or CPNE. CG bond to dentin is improved with acid etching using phosphoric acid. However, PLP provided no significant improvement in the shear bond strength of DAP and CG.

Acid Etching, Dental↗
PubMed1992

Shear bond strengths of ten dentin adhesive systems.

This in vitro study tested the shear bond strengths of nine third-generation dentin bonding systems. All of these systems had higher bond strengths than the control, a second-generation agent. Amalgambond and All-Bond had the strongest bonds to dentin, 23.3 +/- 5.7 and 19.3 +/- 5.6 MPa, respectively. Clearfil Photo Bond and Prisma Universal Bond 3 had intermediate bond strengths (approximately 13 MPa). Gluma, PowerBond, Scotchbond 2, Tenure, and XR-Bond all had mean shear bond strengths of less than 8 MPa.

Analysis of Variance↗
PubMed2003

Shear bond strengths of laboratory-cured prosthetic composite to primed metal surfaces.

PURPOSE: To examine the effect of using metal primers to enhance the shear bond strength of a laboratory-cured prosthetic composite to cast metal surfaces. METHODS: Cast discs (10 mm diam., 2.5 mm thick) were prepared from high gold-containing alloy, Ag-Au-Pd alloy, and commercially pure titanium (CP Ti). After casting, the surfaces of the discs were sandblasted with 50 microm Al2O3. Each surface to be bonded was treated with one of four types of metal primers: V-Primer (VP), Metal Primer II (MP), Cesead II Opaque Primer (OP), and an experimental primer (EP). Specimens without primer were prepared as controls. After tape with a circular hole (5 mm diam.) was fixed on the disc surface to define the bonding area, the opaque resin was applied within the hole and light-cured according to the manufacturer's instructions. After polymerization of the opaque resin, a layer (1 mm thick) of each dentin and enamel resin was applied separately using Teflon matrices (6 mm I. D.). The bonded specimens were immersed in 37 degrees C water for 24 hours (baseline) and were then thermocycled for 5,000 and 10,000 cycles. The shear bond strengths were determined at the baseline and after thermocycling. The results were analyzed using ANOVA/Bonferroni/Dunn's test (c = 0.05). RESULTS: There were no statistical differences (P > 0.05) in the shear bond strength among surface applications for the gold alloy at the baseline. After 5,000 and 10,000 thermocycles, the gold alloy specimens primed with OP and EP primers exhibited higher bond strength compared to those primed with VP and MP primers, and the non-primed control specimens. The Ag-Au-Pd alloy specimens tended to be similar to the gold alloy specimens after each number of thermocycles. The shear bond strengths to CP Ti primed with OP and EP were significantly (P < 0.05) higher than the others after 5,000 and 10,000 thermocycles.

Analysis of Variance↗